1. Field of the Invention
The present invention relates to a system for centrally controlling a plurality of various types of electrical apparatuses such as lighting apparatuses, air conditioners, television sets, and the like by radio communication.
2. Description of the Prior Art
With the prevalence of various convenient and inexpensive electrical apparatuses, many houses or offices currently contain air conditioners, electric stoves and other heating apparatuses, various cooking apparatuses, television sets, cassette recorders with radios, videocassette recorders, stereo sets and other audio-visual apparatuses, as well as many other electrical apparatuses. However, it is natural to want to individually control these electrical apparatuses. Even if a remote controller or the like is provided, one must go to a place where each apparatus is situated to perform control with a dedicated controller. As the number of electrical apparatuses is increasing, for example, more time is required for turning on the power of each electrical apparatus, setting an operation timer, and turning off the power of unnecessary electrical apparatus, and the number of remote controllers is also increased.
In the circumstances, a home automation system for controlling a multiplicity of electrical apparatuses in a centralized manner has been proposed.
On the other hand, a security system is realized in which in order to monitor security in houses or offices, various sensors are installed indoors and outdoors to perform remote centralized control of smoke or flame detectors, invader detectors, and the like.
In the ordinary centralized control system, however, since control signals are directly exchanged between a control object or electrical apparatus and a centralized control device, the electrical apparatus to be incorporated in the system must be provided beforehand with an exclusive system circuit. Therefore, general-purpose electrical apparatuses need to be changed in design when they are incorporated in the system. Furthermore, the apparatuses for the system need to be provided with the exclusive circuits, which unavoidably increases the apparatus cost.
On the other hand, a case where an electrical apparatus purchaser does not want to introduce its system and just wants to have an intrinsic function of the electrical apparatus or a case where the purchaser has already introduce a different type of system is also assumed. In this case, the exclusive function of the electrical apparatus for the system is unnecessary for the purchaser, and the electrical apparatus whose price is set high because of its adaptation to the system may not be attractive.
Moreover, in the centralized control system, an installation type computer device or the like is usually used to carry out control. When control conditions/contents are changed, it is necessary to go to a predetermined place where a controlling computer is installed, and perform processing at that place. For example, when the control object or electrical apparatus is a rice cooker, a washing machine, a lighting apparatus, an air conditioner, or another so-called home electrical product, a television set or a videocassette recorder, the control conditions may be changed daily. Therefore, it is troublesome to go to the controlling computer installation site every time change is required. For the centralized control of various types of electrical apparatuses, control items are limited, and the use of a system cannot be realized.
In the aforementioned security system or the like, when the system is introduced, installation work, wiring work, or another large-scale work is necessary for sensors, communication devices or the like, and installation cost often becomes high. Therefore, system introduction is not considered until a new building needs to be constructed, which causes a problem that it is difficult to popularize the system.